Fire extinguisher



April 15, 1941. E E RTZ 2,238,693

FIRE EXTINGUISHER I Filed ua 16, 1938 Z1 70 Geeriz Patented Apr.- 15, 1941 FIRE EXTINGUISHER Eric Geertz, Aurora, 111., assignor to Cardox Corporation, Chicago, 11]., a corporation of Illinois Application May 16, 1933, Serial No. 208,296

12 Claims.

This invention relates to new and useful improvements in fire extinguishers.

The primary object of the invention is to provide an improved form of hand held portable fire extinguisher which is particularly adapted for employing carbon .dioxide as the sole or primary extinguishing medium.

A further important object of the invention is to provide an extinguisher of the above noted character which is constructed insuch a man'- ner as to effect delivery of liquid carbon dioxide to the discharge head, or the like, of the same at all times regardless of the angle or position in which the extinguisher is held during use.

A still further important object of the invention is to provide a form of discharge means for liquid carbon dioxide which will bring about a drop in pressure to atmospheric pressure while the carbon dioxide'is passing therethrough; which will retard or restrict the rate of fiow oi the discharge sufflclently to maintain within all restricted passages, or the like, leading up to the said discharge means, a pressure which is sufiiciently high to prevent the formation of snow which would clog up said passages, and which will result in discharging a very uniformly dense cloud of low temperature carbon dioxide gas with fine particles of snow mixed therewith and with the said discharge occurring at a sumciently low velocity to avoid entrainment of air.

Other objects and advantages of the invention so as to permit the operator of the extinguisher to hold the same with the discharge end in teasonably close proximity to the fire while his person is positioneda safe distance from the fire.

One end of the pressure container 5 is provided with an internally threaded discharge opening 6 in which is mounted the threaded stem 1 of a coupling body 8. This coupling body is provided with an enlarged bore portion 8 of tapered formation. This bore terminates in a valve seat ill at its inner end with a reduced or restricted duct H extending from the center of the valve seat ID to the end face of the stem 1.

' parallelism with the duct I3. One end of the will be apparent during the course of the fol-.

lowing description.

In the accompanying drawing forming a part of this specification and in which like numerals are employed to designate like parts throughout the same, the figure is a longitudinal sectional view of the portable fire extinguisher embodying this invention.

In the drawing, wherein for the purpose of illustration is shown the preferred embodiment of this invention, the reference character 5 designates an elongated pressure container which is constructed of proper material to provide a strength factor sufficient to hold carbon dioxide at atmospheric temperatures and their correduct l5 passes through a surface of the coupling 8 and is closed by the threaded plug ll. The duct l6 extends entirely through the wall of the coupling from the outer surface of the same into the bore 9. The outer end of this duct I is closed by the plug it. It will be appreciated that the arrangement of ducts l2, l3, l5 and i8 is such that they may be cored in the coupling when thelatteri is cast, or they may be drilled after the coupling 8 is formed. The plugs it, it and ii are necessary to close the outer ends of the ducts it, it and it. These various ducts l2, l3, l6 and i6 form a passage between the tapered bore 9 and the end face of the coupling stem I.

The open'end of the duct l2 has threaded therein one end of a dip tube i9 which extends to the opposite endportion of the chamber formed in the container 5. With this arrangement, it will be seen that the passageway H affords communication between one end of the container chamber and the bore 9 of the coupling, while the dip tube l9 and the series of ducts I2, I3. I5 and I 6 form seat ill whenever the extinguisher is arranged.

in any position where the valve seat I0 is located above a horizontal plane passing through the container. When the valve seat I 0 is arranged below such a horizontal plane, the ball valve- 20 will be unseated. In other words, the ball valve 20 will remain on its seat at all times except when the extinguisher is inverted beyond an angle where the axis of the container 5 is arranged in a true horizontal plane.

The purpose of the mechanism so far described is to assure feeding of liquid carbon di-- oxide to the bore 9 of the coupling member I regardless of the position in which the fire extinguisher is held while in use. With the extinguisher in an upright position, or in any position in which the ball valve is seated, the

weight of the said valve is sufllcient to cause'the same to be seated by gravity becauseof the equalized pressure on opposite sides of the valve. With the duct ll sealed by the ball valve 20, the gas above the liquid in the container l-will force liquid carbon dioxide upwardly through the dip.

tube It and the series of ducts l2, l3, l5 and it into the coupling bore 9. If the container 5 is inverted, or moved into a position where the valve 20 will not seal theduct ii, the said valve will leave its seat. Insuch a position, however, the liquid carbon dioxide in the container 5 has moved to the other end portion of the container and the admission end of the duct I i will be covered by the liquid. Liquid then will flow through the duct ll into the bore 8 and past the ball valve 20. This flow of liquid through the duct l I will occur notwithstandingthe fact that the gas space at the inverted upper end of the fire extinguisher is in communication with the bore '9 through the dip tube i9 and the series of ducts entirety by the reference character 38. This discharge head includes a two-part casing formed by the base 31 having a series of ducts 38 formed'therein and communicating with the discharge duct 32 of the valve casing and a ring 39 which is threadedly connected to the base 31. Tightly clamped between the ring 39 and the base 3'! is a disc-like block or mass of material All which sufllcient strength to withl2, It, It and It. If the ball valve 20 were not provided for sealing the duct II when the fire extinguisher is in an upright position, gas then would be withdrawn through the duct H rather than liquid through the dip tube l9 and its associated series of ducts.

The outer end of the coupling member B has its bore portion internally threaded at 19 for connection with the stem 20 of a valve casing designated in its entirety by the reference character 2|. This valve casing 2! has an inlet passage 22 which is reduced at its inner end to form a seat 23 for the needle valve 24. This needle valve has an enlarged head 25, at its outer end against handle 3| suitably secured to its outer end so.

that manipulation of this handle will adjust the stem 29 to either force the valve 24 against its seat 28 or to release the said valve so that it may be unseated by its spring 2! and the pressure of the medium confined within the container and the various ducts leading up to the valve. when the valve is unseated, the liquid carbon dioxide will flow from the bore 9 of the coupling 8 stand the pressure applied to the inner face of the same and which is formed with very small, or fine pores uniformly distributed throughoutthe same.

The liquid carbon dioxide released from the pressure container 5 through the coupling 8 and the valve casing 2! passes through the pores of the porous disc 40 and is discharged in the form of a very dense, uniform cloud of low temperature carbon dioxide gas with extremely fine particles of snow mixed therein. The dense but porous disc 40v functions to considerably restrict the flow of carbon dioxide from the extinguisher with the result that the pressure behind the disc is at all times maintained at a relatively high value, such, for example, as 400 to 500 pounds. This dense porous disc 40 never lets the pressure in back of the same drop to the value at which snow will formin the passageways or ducts leading up to the inner face of the disc and clog these ducts or passageways. It will be appreciated that snow will form at approximately 75 pounds per square inch pressure.

Besides functioning to prevent an undesirable drop in pressure inwardly. of the-disc to, this dense, porous member also functions to cause the pressure of the discharging carbon dioxide to drop to atmospheric pressure while passing through the disc. The discharge of the very dense cloud of low temperature carbon dioxide gas and fine particles of snow is at a sufilciently low velocity as to avoid entrainment of air in the discharging stream of carbon dioxide gas.

It will be appreciated that the disc 40 may be formed of numerous different materials and combinations of materials and in many different ways to provide the desired characteristics; namely, a rigid body possessing sufllcient strength to withstand the internal pressure applied thereagainst and with the body possessing extinguishing medium to the atmosphere at a through the duct 22 and pastthe valve 14 into the outlet duct 32.

A branch duct u communicates with the inlet duct 22 of the valve casing and is closed at its outer end by means of a rupturable disc 34' which is held in place by means of a plug 88. Should the pressure of the carbon dioxide within the container I rise to a dangerous value-thedisc 81' will rupture and relieve the pressure.

Mounted on the nipple of the valve casing II which has-the discharge ductfl formed therein is a discharge head which isdesignated in its sufllciently low velocity to avoid entrainment of air in the discharging stream. e

As an example ofan extremely suitable disc structure, it has been determined that an or-.

dinary vitrified, silicate bonded grinding wheel formed of grit sizes varying from No. 46 to No. 120 and with the disc body varying in thickness from one-half inch to one and one-half inches is very satisfactory. It is possible to obtain very V extinguisher of the character specifically (M8- closed. and described herein, the intermediate grit sizes, numbered-60, and appear to be the best or most preferred sizes. Thebest results have been obtained with disc thicknesses graduating from one inch upwards. The preferred diameteis'of the disc willrange from two and one-half inches to four inches. It has been and the pressure maintained behind the porous body may be varied by altering the diameter, the thickness and the degree of porosity of the disc body.

It is to be understood that the form of this invention herewith shown and described'is to be taken as a preferred example of the same, and

that various changes in the shape, size, and ar rangement of parts may be resorted to without departing from the spirit of the invention or the scope'oi the sub-joined claims.

Having thus described the invention, I claim:

1. In a fire extinguisher, an elongated pressure container for carbon dioxide at atmospheric temperature and its corresponding vapor pressure and having a discharge opening at. one end, a valve device for controlling discharge of the carbon dioxide from the container, means constructed and arranged to feed liquid carbon dioxide irom the container to the valve device regardless of the position in which the container is held duringuse, a discharge head iormingan expansion chamber opening directly to the .atmosphere attached to the valve device to receive liquid carbon dioxide therefrom when said device I t g v a',saa ,ecs

determined that the character or the discharge said head through which the carbon dioxide passes iustprior to being discharged in said unconfined condition to the atmosphere. I

5. In a fire extinguisher, a pressure container for carbon dioxide, means for controlling discharge irom said container, means for supplying liquid carbon dioxide to said control means, a

discharge head attached to said control means to receive liquid carbon dioxide from the control means when it is conditioned for fluid fiow, and

rigid porous means in the discharge head conof air.

6. In a fire extinguisher, atpressure container for carbon dioxide, means for controlling disis conditioned for fluid flow, and porous means practically filling the expansion chamber of .the

discharge head constructed and arranged to effect discharge of a uniformly dense cloud of low temperature carbon dioxide gas mixed with fine particles of snow at a sufliciently low velocity to avoid entrainment oilair and to restrict the discharge trom the container to a rate of flow sulficiently low to prevent such a drop in pressure inwardly of said discharge head expansion chamber as would result in the formation of snow.

charge from said container, means for supplying liquid carbon dioxide to said control means, a discharge head attached to said control means, and a rigid body or fine porous material in said head through which the carbon dioxide passes inv being discharged to the atmosphere.

7. In a fire extinguisher for discharging liquid carbon dioxide, a hollow discharge head adapted to receive liquid carbon dioxide and to discharge direct to the atmosphere a dense cloud of gas and snow incapable oi entraining air, and a rigid 2. In a fire extinguisher, an elongated pressure container for carbon dioxide and having a discharge opening at one end, a valve device for controlling discharge oi the contents of the container, means constructed and arranged to feed liquid carbon dioxide from the container to the valve device regardless of the position in which the container is held during use, a discharge head attached to the valve device, and a rigid body oi fine porous material in said discharge head fiuid flow, and rigid porous means in the discharge head constructed and arranged to eiIect discharge of a uniformly dense cloud of low'temperature carbon dioxide gas mixed with fine particles of snow at a suificiently low velocity to avoid entrainment of air and to restrict the discharge from the container to a rate oi flow sumciently low to maintain a pressure value inwardly, of the discharge head meansabove that at which snow will form.

body of fine, porous material entirely filling the cross-sectional area 0! the cav; ;y of said head through which the car-bon dioxi-ze passes in being discharged to the atmosphere, the porosity'and thickness of said body causing the liquid carbon dioxide to be converted to the dense gas and snow in passing therethrough.

8. In a fire extinguisher for liquid carbon dioxide, means providing a passageway for said carbon dioxide between a source of supply and a point of discharge, and discharge means at the outer end of said passageway forming means through which the carbon dioxide passes and from which it is discharged to the atmosphere'in an unconfined condition and at a sufficiently low velocity to avoid entrainment of air, said discharge means comprising a fine porous body possessing suflicient strength to withstand the pressure of the liquid carbon dioxide applied thereagainst and having the proper porosity characteristics to efiect a combined gas and snow discharge of a uniiorm density.

9. In a fire extinguisher, a source of liquid carbon dioxide under high pressure, means for con- 4. In a fire extinguisher, an elongated pressure container for carbon dioxide and having a disducting the said liquid to a point or discharge, and means at'saidpoint of discharge for effecting delivery or the carbon dioxide to the atmosphere in the form of a uniformly dense cloud of mixed gas and snow at a sufilciently low velocityto avoid entrainment of air, said last mentioned means including a porous body possessing suiiicient inherent rigidity and strength to withstand ,the pressure of the carbon dioxide without being deformed.

10. In a fire extinguisher, a source of liquid carbon dioxide under high pressure, means for conducting the said liquid to a point of discharge, and means at said point oi discharge for efiecting delivery of the carbon dioxide to the atmosphere inan unconfined condition in the form of a uniformly dense cloud 01' mixed gas and snow at a sufiiciently low velocity to avoid entrainment of air, said last mentioned means including a porous body formed of bonded grit particles;

11. In a fire extinguisher, a source of liquid carbon dioxide under high pressure, means for conducting the said liquid to a point of discharge. and means at said point of discharge for eilecting delivery of the carbon dioxide to the atmosphere in the form of a uniformly dense cloud of mixed gas and snow at a sufficiently low velocity to avoid entrainment oi air, said last mentioned means including a rigid porous body which may vary in thickness ,irom one-half to one and one-half inches and in diameter from two and one-half to four inches.

12. In a fire extinguishing device, a discharge head adapted to receive liquid carbon dioxide, and

' a porous body in the discharge head exposed to the liquid carbon dioxide on one side and to the atmosphere on the other and through the pores of which the carbon dioxide passes toeilect discharge of a uniformly dense cloud of low temperature carbon dioxide gas mixed with line particles of snow at a sumciently low velocity to avoid entrainment of air and to restrict the. dis-- charge to a rate sumciently low to prevent such a drop in pressure inwardly of said discharge head as would result in the formation of snow. 

